The present invention relates to jewelry safety clasps for use with jewelry items such as necklaces, bracelets, etc. More specifically, the present invention relates to a jewelry safety clasp that has a primary locked position and a safety locked position to prevent the inadvertent opening of the clasp.
Jewelry safety clasps for selectively securing the ends of a chain together are known. One type of clasp is described in U.S. Pat. Nos. 4,001,923 and 4,286,360. In these patents there is described a clasp having a male and a female member which are adapted to be clasped together by releasable locking means engaging the male member to hold it within the female member. The locking means is disposed in the female member and includes an integral one piece member having a locking portion for engaging the male member, a resilient portion for biasing a locking portion against the male member, and an actuating portion for moving the locking portion relative to the pressure of the resilient portion for releasing the male member, to thereby permit retraction thereof from the female member. The female member also includes holding means to position the resilient portion relative to the female member.
In this clasp, should the actuating portion be inadvertently actuated, for example, by an undesired external force, the female member will retract from the male member, often without the person wearing the jewelry item being aware that the clasp has opened. Thus, the person runs the risk of losing the jewelry item.
Attempts have been made to provide a clasp with a safety catch. Among these attempts are the use of a separate chain that is fixedly attached to either the male or female member. The free end of the chain is attachable to the other member. Thus, should the clasp inadvertently open, the chain serves to keep the male and female members connected together. This type of safety chain requires the use of additional material, which can detract from the appearance of the clasp. In addition, the connection of the free end of the chain to the other member is usually an interference fit that deteriorates over time.
Thus, it is an object of the present invention to provide a jewelry safety clasp that prevents the inadvertent opening of the clasp.
The jewelry safety clasp in accordance with the present invention achieves the above and other objects in a currently preferred exemplary embodiment that includes a female member and a male member. The female clasp member includes a hollow housing, and a locking member slidably connected to the housing. The locking member has a push button disposed at one end thereof that projects through an opening in the housing. The locking member slides between a first locked position and a second unlocked position. A spring biases the locking member into the locked position. The male clasp member includes a shaft having a first reduced diameter portion adjacent to its free end and a second reduced diameter portion spaced from the first reduced diameter portion. In the locked position, the shaft is received within the housing with the locking member disposed about the second reduced diameter portion, thereby preventing said shaft from moving axially with respect to the housing.